Telephone-exchange system.



A. E. REINKE.

TELEPHONE EXCHANGE SYSTEM. APPLICATION man APR. 26. 1916.

1,203,407. Patented Oct 31,1916.

h v ML 1 H- IIHI" v /m e/7f0r.- Arfhur E. Rein/re.

UNITED STATES rarer prion;

ARTHUR E. REINKE, 0F DULWICH, LONDON, GLAND, ASSIGNOR TO WESTERN ELEC- TRIO COMPANY, INCORPORATED, OF NEVT YORK, N. Y., A CQRPOBATION OF NEW YORK.

Application filed April 26, 1916.

2 '0 all whom it may concern Be it known that I, ARTHUR E. REINKE, a citizen of the United States, residing at Dulwich, London, England, have invented certain new and useful Improvements in Telephone-Exchange Systems, of which the following is a full, clear, concise, and exact description.

This invention relates to telephone exchange systems, and more particularly to such systems of the central energy type in which duplicate answering jacks are used.

It is the object of this invention to provide an improved arrangement of circuit and apparatus at an operators position,

whereby the efficiency of such systems may be increased and the work of the attending operator simplified.

The principal feature of this invention provides means, whereby, while a telephone circuit is in use, forming a part of a connection between subscribers, a second connection may be prepared utilizing a part of such telephone circuit, the breaking-down of the first connection serving, without any further operation on the part of the operator, to establish the connection desired. More specifically, this feature involves the use in connection with the toll trunk line of duplicate answering jacks associated with one end thereof, one of which answering jacks may be used in preparing the second connection while the first connection is established over the other of such answering jacks, and also a relay system, associated with such answering jacks, serving alternately to render one of said answering jacks operative for the establishment of the connection at the time when the use of the other answering jack is discontinued.

A further feature of the invention involves an improved and novel arrangement of circuits and apparatus by which the toll trimk line may be utilized both by the answering toll operator and a multiple toll operator, whereby the answering toll operator may establish successive connections over the toll trunk line without the removal of the busy guard from the test conductor of the toll trunk line-where it appears in the multiple jack.

The drawings show a preferred embodiment of the invention.

The toll trunk line 1, 2, has associated therewith a pair. of answering jacks 3, 4,

Specification of Letters Patent.

TELEPHONE-EXCHANGE SYSTEM.

ratenteaoet. e1, 191s.

Serial No. 93,797.

such toll trunk line being extended through the normally closed springs 5, 6, and 7, 8 of the usual transfer jack 9 and the conductors 10 and 11 to the armatures of the relays 12, 13. When the relay 12 is energized, the circuit of the toll trunk line is further extended through the front contacts 14, 15, thereof to the spring 16, 17 of the answering jack 3. When the relay 13 is energized, which as hereinafter appears can only be the case when the relay 12 is deenergized, and vice versa, the toll trunk line is extended through the front contacts 18, 19, of such relay 13 to the spring 20, 21 of the answering iack 4. The toll trunk line is also normally connected, that is, when the springs 5, 6, and 7, 8 of the transfer jack 9 are closed, to the springs 22, 23 of the various multiple jacks 24.

Connected to the sleeve contact 25 of the answering jack 3, is a relay 26, the circuit of which also includes the back contact of the lower armature of the relay 27 which is connected to the sleeve contact 28 of the answering jack 4, and the circuit of which includes also the lower contact of the armature of the relay 26. The relay 26 controls by its upper armature the circuit of the relay 12 and, correspondingly, the relay by its upper armature, controls the circuit of the relay 13.

A test control relay 29 is connected to the front contacts of the lower armatures of the relay 26, 27 so that upon the energization of either relay the relay 29 will be energized.- -This relay by its armature 30 in its retracted position closes a circuit from ground, through the relay 31 and also through the normally closed contacts 32, and 33 of the transfer ack 9, to the test conductor 34 leading to the sleeve contacts 35 of the multiple jacks of the toll line. This ground connection, so long as it exists, indicates the idle condition of the toll line to the multiple jack toll operators. When the relay 31 is energized and the relay 29 is deenergized, that is, when the trunk line is in use in a connection established by the multiple operator, a circuit will be closed over the armature 36 of the relay 29 and the left-hand armature of the relay 31 for the busy signal lamp 37 adjacent the answering jacks 3 and 4 upon the answering toll operators position. A calling signal 38 is also associated with the answering jacks 3, 4 and is controlled by the locking relay 39 which will be initially energized upon the receipt of signal current over the trunk line as will be hereinafter described.

The answering toll operators cord circuits may be of any desired arrangement and construction, provided that battery is connected to the sleeve of the answering plugs thereof, when the cord circuits are in use. The multiple toll opcrators cord circuit may also be of any desired construction with the further provision of a cut-out key 10, which, when operated, opens the talking conductor of the cord circuit and closes at the contacts 4:1, 42, one opening in the circuit of the signal 43, which signal is adapted to become active upon the energization of the relay a4, connected to the sleeve contact of the plug 45. This relay L4 is provided with two windings, one of which is adapted to be shunted upon the energize,- tion of such relay. The resistance of the two windings of relay at of the various multiple operators cord circuits, are so adjusted that if the toll line is already in use at some other point, insuflicient current will pass through the two windings of the relay 4:4 in series to energize it. If, however, it is not in use at some other point, and the ground connection is established to the test conductor of the multiple acks as above described, relay 44 will be energized, lighting a lamp :3 and shunting the left-hand winding so that insuflicient current will pass through the two windings of any other relay ll, in series, the plug also associated with which may be inserted in a multiple jack of the same trunk line.

Assuming that the toll line is idle and signaling current isimpressed thereon from the distant end thereof, such signaling current will pass over the conductor 1 of the trunk line, springs 5 and 6, of the jack 9, conductor 10, right-hand armature of the relay 31, leit-hand winding of the relay 39, left-hand armature of the relay 29, conductor 11, springs 7 and 8 of the jack 9 to con ductor 2 of the trunk line. This causes the energization of the relay 39 which attracts its armature and closes a locking circuit for itself, including its right-handwindings, back contact of left-hand armature of the relay 31 and armature 36 and back contact of the relay 29. It also closes in parallel with its locking winding a circuit, to li ht the calling signal 38 so that the answering toll operator is signaled. The answering toll operator thereupon inserts a plug such as 46 into one of the answering jacks 3 or l. In this case it will be assumed that she inserts it in the jack 3; Thereupon a circuit is established from battery over the sleeve of he plug 46, sleeve contact 25 of jack 3, relay 26 and back contact and lower armature of the relay 27. The relay 26 is energized,

tion of its armatures extends the conductors l and 2 of the trunk line to the springs 16 and 17 of the answering jack 3, and therethrough to the plug and talking conductors of the cord circuit, so that the answering operator may, if necessary, converse with the toll operator" at the distant end of the trunk line and establish the desired connection over such cord circuit. The energization of the relay 26 at the same time causes the energization of the relay 29, which immediately attracts all three of its armatures, opening the locking circuit of the relay 39 and the energizing circuit for the la1np38, opening the extension of the trunk line to the left-hand winding of the relay 39, and opening to ground connection to the relay 31 and conductor 34: to the multiple jacks 35 of the trunk line.

'While the connection presumed to have been established as a result of the call just described, is maintained over the answering jack 3 and the plug 46, the answeringoperator may prepare a second connection over the same trunk line by inserting the plug 47 in the other answering ack associated with such trunk line. No connection will be made at this time from the jack %l to the trunk line for the reason that the circuit for the relay 27 is maintained open by the energization of the relay 26, and consequently relay 13 cannot be energized. For the time being, therefore, both the acks 3 and a will have inserted therein plugs such as $6 and t7, the jack 3 and the plug as serving in the established connection and the ack 4: in the plug 47 preparing 'a second connection, which has not as yet been established. When the connection established is no longer required, the operator will break down such connection by removing the plug 46 from the ack 3. The relays 26 and 12 associated with such jack will immediately be deenergized and allow their armatures to retract. Therelay 26, at the back contact of its lower armature, now closes a circuit for the relay 27 including the sleeve con-tact 28 of the jack 4 and the sleeve of the plug 47. This relay 27 thereupon energizes and closes first, a circuit for the relay 29 in place of the one up to this time maintained by the relay 26, and second, a"

circuit for the relay 13, which, by attracting itsarmaturaextends the conductors 12 of the trunk line to the tip and ring conductors of the cord circuit, the plug of which is inserted in the jack 4. Therefore, the connection which was prepared by the insertion of the plug -17 in the jack 4 is now immediately completed upon the withdrawal of the plug -l6 from the jack 3, the deenergization of the relay 12 opening the connection of the trunk line to the jack 3. It will be noted that the interval between the opening of the circuit closed by the front contact and lower armature of relay 26 and the closure of the circuit by the attraction of the lower armature of the relay 27, was too short to permit the relay 29 to decnergize sufficiently for its armature 30 to reach its back contact. The busy condition is therefore continuously maintained on the test conductor 34 associated with the multiple jacks 35.

While the second connection is established, as has just been described, a third connection may be prepared by the insertion of a plug such as 46 in the jack 3 and the operation resultant upon the withdrawal of the plug 47 from the jack 4 will be precisely as has been hereinbefore described, when theplug 46 e was withdrawn, in this case of course, the relays 13 and 27 being deenergized upon the withdrawal of the plug, and the relays 12 and 26 immediately thereafter energized, the relay 29 being maintained energized during this operation.

Assuming that the multiple toll operator desires a connection over the toll line, she

will insert a plug 45 into one of the multiple jacks 24, having first operated the cut-out key 40 in order that there may be no interference with the conversation at that time taking place on the trunk line. If the trunk line is in use through either the jack 3 or the ack 4, the relay 29 is maintained energized and since the armature 30 thereof has been attracted away from its back contact, no circuit will exist at this time for the relay So long as the relay 29 is energized, that is, so long as the answering operator is using the toll line either through the jack 3 or the jack 4, the relay 44 will remain unenergized. Immediately, however, that neither of the jacks 3 or 4 is in service, the relay 29 is without current and a circuit is established through its back contact and armature 30, relay 31, springs 32 and 33 of the jack 9, conductor 34, sleeve contact 35 of a multiple ack 24, sleeve of the plug 45 and the two windings of the relay 44 in series, energizing such relay 44. This relay closes a circuit (the cut-out key 40 having been operated) for signaling lamp 43, which immediately, by lighting, indicates to the operator that she may use the trunk line and she thereupon does so in the usual way which need not be described here. At the time that the relay 44 was energized, the same circuit caused the energization of the relay 31. This relay, by the attraction of its armatures, opens the extension of the trunk line 1, 2 to the relay 39 and closes a circuit for the lamp 37 over the front contact and left-hand armature of relay 31 and the armature 36 and its back contact of the relay 29. This lamp 37, as is obvious, will be lighted continuously while the connection is established over the multiple jack of the trunk line, serves as a busy signal for the answering toll operator and warns her not to attempt to use the trunk line over the answering jacks 3 and 4. hen the connection established over the multiple jack as just described is not longer required, it may be taken down by removing the plug 45 from the jack 24 in the usual manner. This causes the deenergization of the relay 31, and the consequent extinguishment of the busy lamp 37, and the trunk line may now be used either for incoming or outgoing calls by the answering toll operator or for outgoing calls by the same or another multiple toll operator.

If, while the trunk line is being used for a connection over one of the multiple jacks24, a second multiple operator inserts a plug, such as the one 45 into one of the multiple jacks of the trunk line, the relay 44 will not be energized, even though the circuit to ground is completed, over the armature 30 and its back contact of, the relay 29. This is for the reason that the relay 44 of the cord circuit over which the connection is already established, by shunting its left-hand winding has so changed the potential upon the sleeve contacts 35 of the jacks 24 that the relay 44 cannot be energized through its two windings in series. The second operator will, therefore, not receive a false signal by the lighting of the lamp 43, even though she has, as is required, operated the cut-out ke 40 of her cord circuit.

lVhat is claimed is:

1. A telephone exchange system comprising a telephone circuit extending to a central office, duplicate answering acks thereat normally disconnected from the telephone circuit, a plurality of link circuits, a relay associated with each jack, connection of a link circuit with one jack causing the operation of the associated relay and the disabling of the relay associated with the second jack, and a relay operated by the operation of the first relay to extend the telephone circuit to the first jack.

2. A telephone exchange system comprising a telephone circuit extending to a central ofiice, duplicateanswering jacks thereat normally disconnected from the telephone circuit, a plurality of link circuits, a relay associated with each jack, intercontrolled circuits therefor, a second relay controlled by each of the first mentioned relays, connection of a link circuit with one jack causing the operation of the associated relays to extend the telephone circuit thereto and preventing the extension of the telephone circuit to the second jack when another link circuit is connected therewith until after'the first connection is broken down.

3. A telephone exchange system comprising a telephone line extending to a central oilice, duplicate answering jacks and multiple jacks for the telephone line appearing before different operators, a plurality of cord circuits, a signaling device associated with a cord circuit atthe multiple position, and means associated with the answering jacks for preventing the operation of the signaling device when either one or both answering jacks are connected to cord circuits.

f. A telephone exchange system comprising a telephone line xtending to a central oflice, duplicate answering jacks therefor a pearing before an operator, multiple jac (s therefor appearing before other operators, cord circuits located at eachoperators position, a signaling device and relay controlling said device associated with a cord circuit at a multiple operators position, and means associated with the duplicate answering jacks for preventing the operation of the relay when either one or bothanswering ,jacks'are engaged by the plugs of the cord circuits. 7

A telephone exchange system comprising a telephone line extending to a central office, duplicate answering jacks therefor a pearing before an operator, multiple jac s therefor appearing before other operators, cord circuits located at each operators position, a signaling device and a relay associated with amultiple operators cord circuit, and .a relay associated with theduplieateanswering jacks energized when either one :or both. answering jacks are engaged by the plugs of cord circuits,.the first relay :in' its HOIFGIIBLglZBCl condition cooperating With the. second relay in its energized condition to prevent the operation of the signaling device.

6. A telephone exchangesystem comprising a telephone line-extending to a central oflice, duplicate answering acks therefor appearing before an operator, multiple jacks therefor appearing before other operators, cord CH'CHItS located ateaclroperatorls position, a signaling device associated with a multiple operators cord circuit, a relay-also associated therewith seriung when energized to cause the operationsof the signaling device,-and a relay associated with the answering jacks and energized when either one or ARTHUR E. REINKE.

Gopies'of this patent maybe obtained for five cents each, by addressing the Commissioner of Patents, Washingtoznl). G. 

